This invention relates generally to a sprayer assembly adapted to be connected to a source of pressurized carrier liquid, and is adapted to be mounted to a container of chemical liquid to be siphoned into the stream of carrier liquid in a valve open position.
There are a variety of sprayer assemblies arranged to be mounted on a container of liquid chemical and coupled to the end of a hose for drawing an amount of the liquid chemical into the water path through a venturi effect or by the provision of an air gap. A rotatable valve, manually operable, is designed to turn the sprayer on as the carrier liquid inlet and the product inlet are connected, to turn the sprayer off by disconnecting the product inlet and carrier liquid inlet, and to provide for rinsing in which the carrier liquid passage is connected to discharge.
It is important to vent the container to atmosphere in the ON position of the sprayer while chemical liquid product is being drawn into the liquid carrier stream.
The vent control is on the rotary valve within valve chamber of the sprayer housing in accordance with U.S. Pat. Nos. 6,578,776 and 6,672,520 which, as pointed out in the aforenoted related application 60/515,416, allows for unwanted seepage of carrier liquid into the chemical container during the vent open position which is, of course, most undesirable. If such seepage is allowed to persist the liquid chemical will become so diluted that it could lose its effectiveness when spraying garden shrubs and the lawn with a selected chemical. The invention set forth in the aforenoted related application solves this problem by isolating the carrier liquid/chemical liquid connection from the vent and vent control, thereby avoiding the aforementioned dilution problem.
It would be desirable to provide another solution to venting of simple construction which is easy to use and assemble yet highly effective in providing for reliable vent control. And avoids any possibility of seepage of carrier liquid into the container in a vent open condition.